The parent company of Caledonian MacBrayne, David MacBrayne Ltd (DML), tendered to run services to Sweden's largest island, Gotland, in the Baltic off the Swedish mainland.
It also bid to run the Woolwich Ferry, the free vehicle service across the River Thames financed by London River Services, part of Transport for London.
Neither bid was successful but a company spokesman said the process had whetted its enthusiasm for future ferry bids.
"The future of the company and the job security of around 1400 employees rests on its ability to secure new contracts," he said.
Although wholly owned by the Scottish Government, the spokesman said DML was set up as a private firm in 2006 to bid for ferry contracts including the Clyde and Hebrides Ferry Services (CHFS) .
The Gotland service had been particularly attractive, he said: "It was a close match to our existing operations, combining lifeline and tourism ferry services."
Despite its rejection he said the Swedish transport body commented on the excellence of the bid and complimented the company's innovative approach and expertise with island ferries.
He said the cost of bids was commercially sensitive but it would be met by DML. The bids had the full backing of Scottish Ministers.
The Tories, meanwhile, say the Scottish Government should open up CalMac's routes on the Clyde and to the Hebrides to let Swedish or English ferry companies to tender for them.
Alex Johnstone, the Scottish Tories' transport spokesman said he was happy for DML to bid for foregn contracts, but added: "What worries me more is the way that DML or CalMac live in a rather protected environment."
He said offering the Clyde and Hebrides contract one bundle effectively excluded other bidders.
"Just as DML could bid for the Gotland contract, I would like an environment which allowed a Swedish ferry company to bid for a CalMac route."
A Transport Scotland spokesman said EU rules meant companies from across Europe could tender for CHFS, and added: "Extensive analysis as part of the Scottish Ferries Review concluded there is no compelling case to unbundle the Clyde and Hebrides routes."
CalMac ran the Ballycastle to Rathlin Island service for the Northern Ireland Office from 1996 until 2008.